Figure B There are four records with Null Region values. Figure D This time, the query returns Region values that aren't Null. Editor's Picks. The best programming languages to learn in Check for Log4j vulnerabilities with this simple-to-use script. TasksBoard is the kanban interface for Google Tasks you've been waiting for. Paging Zefram Cochrane: Humans have figured out how to make a warp bubble.
Show Comments. Hide Comments. These blank values are called nulls, and you need to handle them carefully. If you want to write a filter condition that catches null values, simply type this text into the criteria box:. This condition matches any fields that are left blank. Use this on the CustomerID field in the Orders table to find any orders that aren't linked to a customer. Or ignore unlinked records by reversing the condition, like so:.
Sometimes, you don't want to specifically search for or ignore null values. Instead, you want to swap those values with something more meaningful to the task at hand. Returns records of transactions that took place during the current week. A week starts on Sunday and ends on Saturday. Returns records of transactions that took place during the last week. Returns records of transactions that will take place next week. Returns records of transactions that took place during the last 7 days.
Returns records for the current month. Returns records for the previous month. A month's worth of sales records. Returns records for the current quarter. Returns records for the previous quarter. Returns records for the next quarter.
Returns records for the current year. Returns records of transactions that took place during the previous year. Returns records of transactions with next year's date. Returns records of transactions with dates that fall between Jan 1 of the current year and today. Tested for a Yes value. A value of 1 or -1 is converted to "True" in the Criteria row after you enter it.
Tested for a No value. A value of 0 is converted to "False" in the Criteria row after you enter it. Attachments In the Criteria row, type Is Null to include records that do not contain any attachments.
Type Is Not Null to include records that contain attachments. Lookup fields There are two types of Lookup fields: those that look up values in an existing data source by using a foreign key , and those that are based on a list of values specified when the Lookup field is created.
Lookup fields that are based on a list of specified values are of the Text data type, and valid criteria are the same as for other text fields. The criteria you can use in a Lookup field based on values from an existing datasource depend on the data type of the foreign key, rather than the data type of the data being looked up. For example, you may have a Lookup field that displays Employee Name, but uses a foreign key that is of the Number data type.
If you do not know the data type of the foreign key, you can inspect the source table in Design view to determine the data types of the field. To do this:. The data type for each field is listed in the Data Type column of the table design grid. Multivalued fields Data in a multivalued field are stored as rows in a hidden table that Access creates and populates to represent the field.
In query Design view, this is represented in the Field List by using an expandable field. To use criteria for a multivalued field, you supply criteria for a single row of the hidden table. Just below the name of the field, you will see a field representing a single value of the multivalued field. This field will have the same name as the multivalued field, with the string.
Value appended. Drag the multivalued field and its single value field to separate columns in the design grid. Intel Inside Celeron. Halls Of Undermountain Maps.
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